Estimativa da Capacidade de Suporte em Corpo Hídrico Urbano de Pequeno Porte

Abstract

Water pollution is a reality in many Brazilian cities. Polluters must be responsible for identifying and quantifying the environmental, social, and economic impacts generated, in order to ensure multiple uses in terms of water quantity and quality for future generations. In this context, a practical methodology for assessing the support capacity of polluted urban water bodies is essential for environmental decision-making. This paper covers the bibliographic survey stage for characterizing the Mumbuca stream basin, Monte Carmelo, Minas Gerais, and defining the water topology; fieldwork stage for defining hydrogeometric characteristics, water sampling and flow measurements; laboratory analysis stage for diagnosing water quality; and computational modeling for calibrating the water quality model and studying the support capacity. The main results indicate that the Water Quality Index is poor and/or very poor in a stretch of the Mumbuca stream downstream of the confluences with the illegal connections of domestic sewage. The statistical metric of the Mean Absolute Error highlighted the need to maintain a reliable baseline of measured data to adjust the water quality model. The maximum admissible loads for the clandestine connections to domestic sewage were 107.12 kgDBO/day, 11.28 kgAmmonia/day and 0.09 kgTotal Phosphorus_l/day. Given the pollution scenario, managers should propose the elimination of clandestine connections of domestic sewage in the reviewed Municipal Basic Sanitation Plan.